As a result, the increase in matrix protein synthesis and decrease in matrix proteinase activity, owing to the TGFβ activity, contributes to the remodeling of the tumor ECM and can result in a fibrotic response, known as desmoplasia, which is commonly observed in many types of tumors and particularly in pancreatic, colon and breast cancers as well as in various sarcomas (155,156). The gene discussed is TGFB1; the disease is breast cancer.